Environmentally responsive Paecilomyces lilacinus microbead and preparation method thereof

ABSTRACT

An environmentally responsive  Paecilomyces lilacinus  microbead and its preparation method and application are provided. The  Paecilomyces lilacinus  microbead includes a capsule core and a capsule wall; wherein, in the capsule core,  Paecilomyces lilacinus  spore powder, a vegetable oil, glucose, peptone, a cellulose nanofiber, sodium citrate, and a surfactant are combined to form an emulsifiable capsule core; and in the capsule wall, chitosan, gelatin, polyvinyl alcohol, glycerol, and water are combined to form a water-responsive shell. The environmentally responsive  Paecilomyces lilacinus  microbeads can stimulate the dissolution of polyvinyl alcohol in the shell according to the moisture content in the soil, so that the water in the soil flows into the microbeads. The cellulose nanofibers in the microbeads absorb water and expand, blocking the holes in the shell, resulting in the inability of spores to flow out.

CROSS REFERENCE TO THE RELATED APPLICATIONS

This application is based upon and claims priority to Chinese PatentApplication No. 202011029908.7, filed on Sep. 27, 2020, the entirecontents of which are incorporated herein by reference.

TECHNICAL FIELD

The invention relates to an environmentally responsive Paecilomyceslilacinus microbead and its preparation method and application,belonging to the technical field of agricultural microorganism.

BACKGROUND

Paecilomyces lilacinus (P. lilacinus) is an effective egg-parasiticfungus of plant phytopathogenic nematodes in the deuteromycotina,hyphomycetes, and paecilomyces. More than 50 species have been found,all of which belong to insect pathogens or nematode pathogens. The studyshows that Paecilomyces lilacinus can not only promote the growth of avariety of plants, but also prevent and control many plant diseases, andit has many advantages including safety, no pollution, high efficiency,and wide host range.

In recent years, climate change worsens, and continuous large-scalerainfall occurs in some areas, resulting in the phenomenon ofprecipitation increase and decrease in different regions and periods,rain and high humidity. This has a significant impact on the periodgrowth and decline of crop diseases and insect pests and disasters inregions. At present, there are three main types of biofertilizers:liquid, powder and granules. These types of biofertilizers can only havea short time effect in farmland. Most of the strains continue toinactivate or lose with the growth of storage time, resulting in fewerstrains that finally reach the roots of crops. As a result, they cannotimprove the growth environment of crops and effectively inhibit thegrowth of pathogenic microorganisms.

SUMMARY

The present disclosure provides an environmentally responsivePaecilomyces lilacinus microbead, which can overcome the shortcomings ofthe existing technologies. The present disclosure provides anenvironmentally responsive Paecilomyces lilacinus microbead, which firstcombine polyvinyl alcohol (PVA) and cellulose nanofibers in themicrobeads. The microbeads in the invention can stimulate thedissolution of polyvinyl alcohol in the shell according to the moisturecontent in the soil, so that the water in the soil flows into themicrobead. The cellulose nanofibers in the microbeads absorb water andexpand, blocking the holes in the shell, resulting in the inability ofspores to flow out. Spores germinate and propagate with the help ofwater and the nutrients in the microbeads. In the process of sporespropagation, the protease and chitinase secreted by Paecilomyceslilacinus can degrade gelatin and chitosan in the shell, and the releaseeffect can be achieved after a certain time. In high-rainfall areas, orin irrigated soil, the microbeads can increase the number of strainsreleased and improve the fertilizer utilization efficiency.

The present disclosure provides an environmentally responsivePaecilomyces lilacinus microbead, the microbead includes a capsule coreand a capsule wall; in the capsule core, Paecilomyces lilacinus sporepowder, vegetable oil, glucose, peptone, cellulose nanofiber, sodiumcitrate, and surfactant were added to form an emulsifiable concentrate(EC) type capsule core; and in the capsule wall, chitosan, gelatin,polyvinyl alcohol, glycerol, and water were added to form awater-responsive shell.

Further, the compositions of each component in the raw material of thecapsule core are as follows (by weight): 20 to 30 portions ofPaecilomyces lilacinus spore powder, 40 to 60 portions of vegetable oil,2 to 3 portions of sodium citrate, 1 to 1.5 portions of surfactant, 1 to1.5 portions of glucose, 0.5 to 1 portions of peptone, and 3 to 5portions of cellulose nanofibers.

Further, the compositions of each component in the raw material of thecapsule wall are as follows (by weight): 1.5 to 2 portions of chitosan,8 to 10 portions of gelatin, 3 to 5 portions of polyvinyl alcohol, 6 to10 portions of glycerol, and 60 to 100 portions of water.

Further, the degree of polymerization of the polyvinyl alcohol is 500 to600.

The invention also offers a preparation method for the environmentallyresponsive Paecilomyces lilacinus microbeads, as follows:

(1) Preparation of core material solution: The Paecilomyces lilacinusspore powder, vegetable oil and sodium citrate were mixed evenly inproportion, and then the surfactant was added in proportion to form EC,and followed by glucose, peptone and cellulose nanofibers to obtain thecore material solution.

Further, the vegetable oil is corn oil, soybean oil or rapeseed oil.

Further, the surfactant is an anionic emulsifier or a non-ionicemulsifier.

Further, the surfactant is a mixture of alkylphenol polyoxyethyleneether, aliphatic alcohol polyoxyethylene ether and sodium lauryl sulfatewith a mass ratio of 2:2:1.

(2) Preparation of wall material solution: Chitosan, gelatin, polyvinylalcohol, glycerol and water were heated and mixed in a proportion of95-100° C., and kept at 95-96° C. to obtain wall material solution.Primary microbeads are obtained.

(3) Inject the core material and wall material solution obtained in step(1) and (2) into the dripping pill machine respectively, adjust thedripping speed to control the ratio of the two, and drip them into thecondensate liquid paraffin.

Further, the dripping speed is 30-60 ml/min, and the inner and outerdiameters of the drip tube orifice are 1-8.0 mm and 1.5-8.5 mm.

Further, the ratio of core to wall in step (3) is 4-5:2-3.

(4) Remove the condensate on the surface of the primary microbeadsobtained in step (3), then dry in a drum at a constant temperature of20-30° C. and a constant humidity of 30%-40% to obtain Paecilomyceslilacinum microbeads.

Further, after drying, the core material and the wall material weights85 percent and 15 percent of the microbead mass, respectively.

Beneficial Effects

1. The inventors of the invention first combine polyvinyl alcohol (PVA)and cellulose nanofibers in the microbeads. The polyvinyl alcohol isapplied into the microbead shell to prepare an environmentallyresponsive shell; cellulose nanofiber is applied with Paecilomyceslilacinus spore powder to formed an EC (emulsifiable concentrate)—typeoil phase, and nutrients such as glucose are added in the core, to embedPaecilomyces lilacinus spore powder. Thus, an environmentally responsivePaecilomyces lilacinus microbead is obtained, can reduce the contactbetween the strain and oxygen, avoid the early recovery of the strain,and protect the strain activity to the greatest extent during storageand transportation.

2. For the water-responsive Paecilomyces lilacinus microbeads, in thesoil with more water content (after irrigation or rainfall), polyvinylalcohol was dissolved in water, so that the water enters the microbeadsand promotes the germination and propagation of spores, and proteasesand chitinases secrete and disintegrate the shell from the inside of themicrobeads, achieving the purposes of slow release, continuous release,and increased number of released species.

3. For the water-responsive Paecilomyces lilacinus microbeads, Cellulosenanofibers in the microbead core can absorb water and adhere to thewall, prevent the leakage of Paecilomyces lilacinus spores embedded inEC, fix the growth and propagation of Paecilomyces lilacinus in themicrobead, thus avoiding the adverse effect of the external environmenton the strain, and protecting the strain activity.

4. The invention adopts sodium citrate cross-linked gelatin and chitosanto increase the gel strength, protect microbeads from the effect ofexternal adverse factors during transportation and storage, and improvetheir storage stability.

5. The invention utilizes proteases and chitinases secreted by strainsduring the growth and propagation in the microbeads to degrade theshell, so as to achieve the purpose of release; the requirement of highbacterial activity release can be achieved only a small amount ofnucleated strains in the microbeads are required, thus reducing theproduction cost.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1: Schematic diagram of structure and function for the product ofthe invention;

FIG. 2: Schematic diagram of sodium citrate cross-linked chitosan andgelatin in the product of the invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In order to make the purpose, technical solution and advantages of thispatent clearer, the following is a further detailed description of thispatent in combination with the particular embodiment. It is understoodthat the particular embodiments described herein are solely for thepurpose of interpreting the patent and are not intended to limit theinvention.

The structure of the environmentally responsive microbead is shown inFIG. 1 and FIG. 2, and the following is further explained in combinationwith specific embodiments.

Embodiment 1: A Water-Responsive Paecilomyces lilacinus Microbead

(1) Preparation of core material solution: 250 g of Paecilomyceslilacinus spore powder, 600 g of corn oil, and 20 g of sodium citratewere added into a beaker and stirred at room temperature for 30 min tomix well, followed by 10 g of the mixture of surfactants dodecylphenolpolyoxyethylene ether, polyoxyethylene lauryl ether, and sodium laurylsulfate (mass ratio 2:2:1); after the formation of EC, 15 g of glucose,10 g of peptone, and 40 g of cellulose nanofibers were successivelyadded and stirred at room temperature for 30 min to obtain the corematerial solution.

(2) Preparation of wall material solution: 1.5 g of chitosan, 10 g ofgelatin, 4 g of polyvinyl alcohol (the degree of polymerization ofpolyvinyl alcohol is 500-600), and 8 g of glycerol were added to 80 mLof distilled water, heated to 95-100° C., mixed well, and kept at 95-96°C. to obtain the wall material solution.

(3) Inject the core material and wall material solution obtained in step(1) and (2) into the dripping pill machine, respectively; the drippingspeed of the capsule core and the capsule wall is 40 ml/min and 30ml/min respectively; drip into the condensate liquid paraffin, removethe condensate on the microbead surface, dry in a 35% constant humidityroller at constant temperature 25° C. to obtain the water-responsivePaecilomyces lilacinus microbeads with core material and wall materialaccounting for 85% and 15% of microbead mass, respectively.

Comparative Example 1: A Water-Responsive Paecilomyces lilacinusMicrobead (Cellulose Nanofiber Deletion Set

(1) Preparation of core material solution: 250 g of Paecilomyceslilacinus spore powder, 600 g of corn oil, and 20 g of sodium citratewere added into a beaker and stirred at room temperature for 30 min tomix well, followed by 10 g of a mixture of surfactants dodecylphenolpolyoxyethylene ether, polyoxyethylene lauryl ether, and sodium laurylsulfate (mass ratio 2:2:1); after the formation of EC, 15 g of glucoseand 10 g of peptone were successively added and stirred at roomtemperature for 30 min to obtain the core material solution.

(2) Preparation of wall material solution: 1.5 g of chitosan, 10 g ofgelatin, 4 g of polyvinyl alcohol (the degree of polymerization ofpolyvinyl alcohol is 500-600), and 8 g of glycerol were added to 80 mLof distilled water, heated to 95-100° C., mixed well, and kept at 95-96°C. to obtain the wall material solution.

(3) Inject the core material and wall material solution obtained in step(1) and (2) into the dripping pill machine, respectively; the drippingspeed of the capsule core and the capsule wall is 40 ml/min and 30ml/min respectively; drip into the condensate liquid paraffin, removethe condensate on the microbead surface, dry in 35% constant humidityroller at a constant temperature 25° C. to obtain the water-responsivePaecilomyces lilacinus microbeads with core material and wall materialaccounting for 85% and 15% of microbead mass, respectively.

Comparative Example 2: A Water-Responsive Paecilomyces lilacinusMicrobead (Polyvinyl Alcohol Missing Set

(1) Preparation of core material solution: 250 g of Paecilomyceslilacinus spore powder, 600 g of corn oil, and 20 g of sodium citratewere added into a beaker and stirred at room temperature for 30 min tomix well, followed by 10 g of a mixture of surfactants dodecylphenolpolyoxyethylene ether, polyoxyethylene lauryl ether, and sodium laurylsulfate (mass ratio 2:2:1); after the formation of EC, 15 g of glucose,10 g of peptone, and 40 g of cellulose nanofibers were successivelyadded and stirred at room temperature for 30 min to obtain the corematerial solution.

(2) Preparation of wall material solution: 1.5 g of chitosan, 10 g ofgelatin, and 8 g of glycerol were added to 80 mL of distilled water,heated to 95-100° C., mixed well, and kept at 95-96° C. to obtain wallmaterial solution.

(3) Inject the core material and wall material solution obtained in step(1) and (2) into the dripping pill machine, respectively; the drippingspeed of the capsule core and the capsule wall is 40 ml/min and 30ml/min respectively; drip into the condensate liquid paraffin, removethe condensate on the microbead surface, dry in a 35% constant humidityroller at a constant temperature 25° C. to obtain 85% and 15% ofmicrobead mass for core material and wall material, respectively.

Comparative Example 3: A Water-Responsive Paecilomyces lilacinusMicrobead (Surfactant Missing Set

(1) Preparation of core material solution: 250 g of Paecilomyceslilacinus spore powder, 600 g of corn oil, and 20 g of sodium citratewere added into a beaker and stirred at room temperature for 30 min andmixed well, followed by 15 g of glucose, 10 g of peptone, and 40 g ofcellulose nanofibers successively and stirred at room temperature for 30min to obtain the core material solution.

(2) Preparation of wall material solution: 1.5 g of chitosan, 10 g ofgelatin, 4 g of polyvinyl alcohol (the degree of polymerization ofpolyvinyl alcohol is 500-600), and 8 g of glycerol were added to 80 mLof distilled water, heated to 95-100° C., mixed well, and kept at 95-96°C. to obtain the wall material solution.

(3) Inject the core material and wall material solution obtained in step(1) and (2) into the dripping pill machine, respectively; the drippingspeed of the capsule core and the capsule wall is 40 ml/min and 30ml/min respectively; drip into the condensate liquid paraffin, removethe condensate on the microbead surface, dry in 35% constant humidityroller at a constant temperature 25° C. to obtain 85% and 15% ofmicrobead mass for core material and wall material, respectively.

Case Effect Test:

(1) Microbead Change and Viable Bacteria Release in Water Environment

Take 30 g of microbeads prepared in Embodiment 1 and ComparativeExamples 1-3, divide them into three portions, place them in a culturedish containing a small amount of sterile water, place them at 28° C.for 5 days, observe the changes in the internal and external structureof microbeads every day, and determine the number of bacterial strainsin the microbeads, the result is Table 1.

TABLE 1 Strain number in microbeads Internal variation Externalvariation (cfu/g) Dayl Embodiment 1 Moisture increased Small amount ofwater 2.4 × 10⁷ adsorption on microbead shell Comparative Moistureincreased Small amount of water 2.2 × 10⁶ Example 1 adsorption onmicrobead shell Comparative No significant change No significant change2.4 × 10⁷ Example 2 Comparative Moisture increased Small amount of water2.3 × 10⁷ Example 3 adsorption on microbead shell Day2 EmbodimentMoisture increased Small amount of water 5.6 × 10⁷ 1 adsorption onmicrobead shell Comparative EC reduced Small amount of water 4.4 × 10⁵Example 1 adsorption on microbead shell Comparative No significantchange No significant change 2.6 × 10⁷ Example 2 Comparative Moistureincreased Small amount of water 2.2 × 10⁷ Example 3 Adsorption onmicrobead shell Day3 Embodiment Moisture increased, trace Small amountof water 6.5 × 10⁸ 1 hyphal growth adsorption on microbead shellComparative Small amount of hyphal Small amount of water 3.3 × 10³Example 1 growth with reduced EC adsorption on microbead shellComparative No significant change No significant change 2.1 × 10⁷Example 2 Comparative Moisture increased, no Small amount of water 2.3 ×10⁷ Example 3 hyphal growth adsorption on microbead shell Day4Embodiment Moisture increased, A small amount of 1.4 × 10⁹ 1 heavyhyphal growth hyphal in the microbead shell and thinning of the shelllayer Comparative Small amount of hyphal Small amount of water 5.8 × 10²Example 1 growth with reduced EC adsorption on microbead shellComparative No significant change No significant change 2.3 × 10⁷Example 2 Comparative Moisture increased, no Small amount of water 2.3 ×10⁷ Example 3 hyphal growth adsorption on microbead shell Day5Embodiment Moisture increased, Small amount of 4.8 × 10⁹ 1 heavy hyphalgrowth hyphal in microbead shell, shell layer breaks ComparativeExtensive hyphal growth Small amount of water 4.4 × 10² Example 1 withreduced EC adsorption on microbead shell Comparative No significantchange No significant change 2.5 × 10⁷ Example 2 Comparative Moistureincreased, no Small amount of water 2.1 × 10⁷ Example 3 hyphal growthadsorption on microbead shell

The test results are shown in Table 1, and the environmentallyresponsive Paecilomyces lilacinus microbeads prepared according to themethod described in Embodiment 1 can adjust the release rate and amountof entrapped viable bacteria according to the moisture content. Whenpolyvinyl alcohol is added into the shell, the polyvinyl alcohol in theshell is dissolved due to the water in the microbead shell, so that theexternal water enters the microbead and promotes the germination ofbacteria cell. When there is no polyvinyl alcohol in the shell but asmall amount of moisture, the external moisture cannot enter themicrobeads. When cellulose nanofibers are added to the core material,cellulose nanofibers absorb water and adhere to the wall, so that theinternal EC encapsulated strains cannot leak, and the strains grow andpropagate inside, so as to achieve the effect of slow release. When theEC core is used (vegetable oil and surfactant were added at the sametime), the strain can grow and propagate normally. When the capsule coreis only a non-EC phase, the strain is wrapped inside the oil phase andcannot contact the external environment for the time being, so it cannotpropagate normally for the time being, resulting in that the straincannot function in a short time.

(2) Effect of Storage Time on Strain Viability:

The samples prepared in Embodiment 1 and Comparative Examples 1-3 weresealed and stored at room temperature for 0-180 days. After storage,take 15 g of the sample, dilute it in 100 g of normal saline, add 0.5 wt% Tween 80, and place it in a conical flask. Shake it with glassmicrobeads (spread flat at the bottom) in a shaker (200 rpm) for 45 min.Then, the strains were diluted with normal saline according to theactivity and number of strains. The dilutions were spread on Rose Bengalmedium, incubated in a 28° C. incubator for 48 h, and counted. As shownin Table 2, the results showed that the strain activity of the productprepared in Embodiment 1 remained well during storage, indicating thatthe microbeads prepared by this method could better protect the bacteriacell during storage. For the product prepared with Comparative Example3, there will be trace loss during storage, due to the use of non-ECtype oil-phase as the core for Comparative Example 3, there will be lossin the presence of non-EC type oil-phase in the spores.

TABLE 2 Storage Comparative Comparative Comparative Time Embodiment 1Example 1 Example 2 Example 3 (days) (cfu/g) (cfu/g) (cfu/g) (cfu/g) 02.4 × 10⁷ 2.5 × 10⁷ 2.3 × 10⁷ 2.1 × 10⁷ 30 2.2 × 10⁷ 1.7 × 10⁷ 2.1 × 10⁷1.5 × 10⁷ 60 2.1 × 10⁷ 1.5 × 10⁷ 1.5 × 10⁷ 1.3 × 10⁷ 90 1.9 × 10⁷ 1.4 ×10⁷ 1.2 × 10⁷ 1.1 × 10⁷ 120 1.8 × 10⁷ 1.3 × 10⁷ 1.1 × 10⁷ 9.8 × 10⁶ 1801.5 × 10⁷ 1.1 × 10⁷   1 × 10⁷ 9.6 × 10⁶

(3) Field Tests

Fertilizer efficacy tests were conducted on the control effect ofroot-knot nematodes, and data collection and analysis were performed onthe test samples. A total of four treatments (Treatment I: Embodiment 1;Treatment II: Comparative Example 1; Treatment III: Comparative Example2; Treatment IV: Comparative Example 3) and an untreated control weredesigned in the experiment. The plants tested are cucumbers. Beforetransplanting, 5 g of prepared samples were added to each soil pit, andother cultivation measures were uniformly and normally operated toensure a consistent plant growth environment. After 30 days ofcolonization, the yield was counted, and at the late harvest stage, theroots were excavated to investigate the root knot index and evaluate thecontrol effect. The control effect is shown in Table 3, and obviouslyEmbodiment 1 can effectively control root-knot nematodes and improvecucumber yield.

Grading criteria for root-knot nematodes:

Grade 0: Healthy roots, no root knots

Grade 1; few root knots, “root knot %”<25%

Grade 2: Moderate number of root-knots, “root knot %”≈25%-50%

Grade 3: High number of root-knots, “root knot %”≈50%-75%

Grade 4: Too many root-knots, “root knot %”>75%Root-knot index=Σ(each grade of disease index×Corresponding number ofdiseased strain/Investigated strain number)×100%Prevention and control effect=(1−Root-knot index in treatmentarea/Root-knot index in control area)×100%

TABLE 3 Root-knot Prevention and Yield index control effect (%) increase(%) Treatment I 19 75.64 25.6 Treatment II 38 51.28 16.8 Treatment III53 32.05  6.9 Treatment IV 41 47.43 10.4 Control 78 — —

Embodiment 2: A Water-Responsive Paecilomyces lilacinus Microbead

(1) Preparation of core material solution: 200 g of Paecilomyceslilacinus spore powder, 400 g of soybean oil, and 25 g of sodium citratewere added into a beaker and stirred at room temperature for 30 min tomix well, followed by 12 g of a mixture of surfactant octylphenolpolyoxyethylene ether and sodium alkyl sulfate (mass ratio 2:1); afterthe formation of EC, 10 g of glucose, 5 g of peptone, and 30 g ofcellulose nanofibers were successively added and stirred at roomtemperature for 30 min to obtain the core material solution.

(2) Preparation of wall material solution: 1.5 g of chitosan, 8 g ofgelatin, 3 g of polyvinyl alcohol (the degree of polymerization ofpolyvinyl alcohol is 500-600), and 6 g of glycerol were added to 60 mLof distilled water, heated to 95-100° C., mixed well, and kept at 95-96°C. to obtain the wall material solution.

(3) Inject the core material and wall material solution obtained in step(1) and (2) into the dripping pill machine, respectively; the drippingspeed of capsule core is 40 ml/min, the dripping speed of capsule wallis 20 ml/min; drip into the condensate liquid paraffin, remove thecondensate on the microbead surface, dry in a 35% constant humidityroller at constant temperature 25° C. to obtain the water-responsivePaecilomyces lilacinus microbeads with core material and wall materialaccounting for 80% and 20% of microbead mass, respectively.

Embodiment 3: A Water-Responsive Paecilomyces lilacinus Microbead

(1) Preparation of core solution: 300 g of Paecilomyces lilacinus sporepowder, 500 g of rapeseed oil, and 30 g of sodium citrate were added toa beaker and stirred at room temperature for 30 min to mix well,followed by 12 g of a mixture of surfactants castor oil polyoxyethyleneether, styrenyl phenol polyoxyethylene ether, and calcium dodecylbenzene sulfonate (mass ratio 3:1:1); after the formation of EC, 12 g ofglucose, 8 g of peptone, and 50 g of cellulose nanofibers weresuccessively added and stirred at room temperature for 30 min to obtainthe core solution.

(2) Preparation of wall material solution: 2.0 g of chitosan, 10 g ofgelatin, 5 g of polyvinyl alcohol (the degree of polymerization ofpolyvinyl alcohol is 500-600), and 10 g of glycerol were added to 100 mLof distilled water, heated to 95-100° C., mixed well, and kept at 95-96°C. to obtain the wall material solution.

(3) Inject the core material and wall material solution obtained in step(1) and (2) into the dripping pill machine, respectively; the drippingspeed of capsule core is 50 ml/min, the dripping speed of capsule wallis 30 ml/min; drip into the condensate liquid paraffin, remove thecondensate on the microbead surface, dry in a 35% constant humidityroller at constant temperature 25° C. to obtain the water-responsivePaecilomyces lilacinus microbeads with core material and wall materialaccounting for 90% and 10% of microbead mass, respectively.

The embodiments above represent only a few embodiments of the invention,the detailed and specific description of which cannot be construed as alimitation of the scope of the patent. It should be noted that, for thegeneral technicians in this field, without separating from theconception of this patent, the aforesaid modes of execution can alsomake several deformations, combinations and improvements, which are allwithin the scope of protection of this patent. Therefore, the scope ofprotection of this patent shall be subject to the claims.

What is claimed is:
 1. An environmentally responsive Paecilomyceslilacinus microbead, comprising a capsule core and a capsule wall;wherein, in the capsule core, Paecilomyces lilacinus spore powder, avegetable oil, glucose, peptone, a cellulose nanofiber, sodium citrate,and a surfactant are combined to form an emulsifiable capsule core; andin the capsule wall, chitosan, gelatin, polyvinyl alcohol, glycerol, andwater are combined to form a water-responsive shell.
 2. Theenvironmentally responsive Paecilomyces Lilacinus microbead of claim 1,wherein parts by weight of compositions of the capsule core are asfollows: 20 to 30 parts of the Paecilomyces Lilacinus spore powder, 40to 60 parts of the vegetable oil, 2 to 3 parts of the sodium citrate, 1to 1.5 parts of the surfactant, 1 to 1.5 parts of the glucose, 0.5 to 1part of the peptone, and 3 to 5 parts of the cellulose nanofiber.
 3. Theenvironmentally responsive Paecilomyces Lilacinus microbead of claim 1,wherein parts by weight of compositions of the capsule wall are asfollows: 1.5 to 2 parts of the chitosan, 8 to 10 parts of the gelatin, 3to 5 parts of the polyvinyl alcohol, 6 to 10 parts of the glycerol, and60 to 100 parts of the water.
 4. The environmentally responsivePaecilomyces Lilacinus microbead of claim 1, wherein a mass ratio of thecapsule core to the capsule wall is (4-5):(2-3).
 5. The environmentallyresponsive Paecilomyces Lilacinus microbead of claim 1, wherein thevegetable oil is one selected from the group consisting of corn oil,soybean oil and grapeseed oil.
 6. The environmentally responsivePaecilomyces Lilacinus microbead of claim 1, wherein the surfactant isan anionic emulsifier or a nonionic emulsifier.
 7. The environmentallyresponsive Paecilomyces Lilacinus microbead of claim 1, wherein thesurfactant is a mixture of alkylphenol polyoxyethylene ether, fattyalcohol polyoxyethylene ether and sodium lauryl sulfate, and a massratio of the alkylphenol polyoxyethylene ether, the fatty alcoholpolyoxyethylene ether and the sodium lauryl sulfate is 2:2:1.
 8. Apreparation method of the environmentally responsive PaecilomycesLilacinus microbead of claim 1, comprising the following steps: (1)preparation of a core material solution: adding and mixing thePaecilomyces lilacinus spore powder, the vegetable oil and the sodiumcitrate to obtain a first mixture, and then adding the surfactant intothe first mixture to form an emulsifiable concentrate, and then addingthe glucose, the peptone and the cellulose nanofiber into theemulsifiable concentrate to obtain the core material solution; (2)preparation of a wall material solution: mixing and heating thechitosan, the gelatin, the polyvinyl alcohol, the glycerol and the waterat 95-100° C. to obtain a second mixture, and performing a heatpreservation on the second mixture at 95-96° C. to obtain the wallmaterial solution; (3) injecting the core material solution and the wallmaterial solution obtained in step (1) and (2) into a dripping pillmachine respectively, adjusting a dripping speed to control a ratio ofthe core material solution and the wall material solution, and drippingthe core material solution and the wall material solution into liquidparaffin to obtain a primary microbead; (4) removing the liquid paraffinon a surface of the primary microbead obtained in step (3) to obtain atreated primary microbead, and performing a drying treatment on thetreated primary microbead in a roller under a constant temperature andconstant humidity to obtain the environmentally responsive Paecilomyceslilacinus microbead.
 9. The preparation method of claim 8, wherein thevegetable oil is one selected from the group consisting of corn oil,soybean oil and rapeseed oil.
 10. The preparation method of claim 8,wherein the surfactant is an anionic emulsifier or a nonionicemulsifier.
 11. The preparation method of claim 10, wherein thesurfactant is a mixture of alkylphenol polyoxyethylene ether, fattyalcohol polyoxyethylene ether and sodium lauryl sulfate, and a massratio of the alkylphenol polyoxyethylene ether, the fatty alcoholpolyoxyethylene ether and the sodium lauryl sulfate is 2:2:1.
 12. Thepreparation method of claim 8, wherein the ratio of the core materialsolution to the wall material solution in step (3) is (4-5):(2-3). 13.The preparation method of claim 8, wherein after the drying treatment, amass percent of the capsule core to the environmentally responsivePaecilomyces lilacinus microbead is 85% and a mass percent of thecapsule wall to the environmentally responsive Paecilomyces lilacinusmicrobead is 15%.